The present invention relates to the field of optoelectronic devices for applications including electromagnetic radiation, in particular detection devices for the detection of infrared radiation (IR). Applications may include gesture detection, security or safety applications, thermal imaging, thermal management, and night vision, for instance.
A passive element directing the propagation of radiation, like a focusing element, can be integrated in the housing or package of an optoelectronic device. If radiation directing elements are produced on a wafer, recesses are formed in one main surface to provide cavities for the accommodation of optical components like radiation sensors, and the radiation directing elements are formed in the opposite main surface.
EP 2 802 009 A1 discloses an imaging device comprising a substrate with an integrated circuit and a cover enclosing a cavity accommodating a sensor. A surface opposite the cavity has a structure directing incident radiation. The structure may be a plate zone or a Fresnel lens focusing infrared radiation and is preferably etched into the relevant surface. At least one through-substrate via may be provided to connect the sensor with a connection pad on the surface of the substrate opposite the cavity.
EP 1 079 613 A2 discloses an image input apparatus with a photoelectric converter element having a flat photosensitive surface and an array of image formation units, which individually receive light beams substantially from an identical area and focus the received light beams on different regions of the photosensitive surface of the photoelectric converter element to form images thereon.
EP 1 267 399 A2 discloses an electronic device having a cap body sealed to a substrate and method for manufacturing the same. An Al film is formed on a cap wafer and patterned into a ring-shaped film. Dry etching is performed to form a drum portion enclosing a recess portion to provide a vacuum dome. The cap wafer is placed on a main body wafer comprising an infrared area sensor. The ring-shaped film is joined to the main body wafer by pressure bonding.
EP 1 612 528 A2 discloses a microstructure infrared sensor focusing radiation on a thermocouple absorbing layer, using a convex lens area made in a photosensitive resist in a recess on the top of the chip cap.
US 2014/0093207 A1 and US 2014/0093213 A1 disclose optical adaptors having monolithically integrated optical elements and micro-mechanical features, the latter defining at least a horizontal reference surface and a vertical reference surface; wherein the horizontal reference surface is perpendicular to an optical plane, the latter being perpendicular the optical axis of the optical elements; and wherein the vertical reference surface is perpendicular to the horizontal reference surface and parallel to the optical axis.
US 2012/0056291 A1 discloses an imaging device including a substrate, a photodetecting portion, a circuit portion and a through interconnect. A lens is arranged on the top surface of the device by means of a holder keeping it in place.
US 2011/0147869 A1 discloses an infrared radiation sensor device including an integrated circuit radiation sensor chip including first and second temperature-sensitive elements connected within a dielectric stack of the chip. A diffractive optical element is integrated with a back surface of the radiation sensor chip to direct infrared radiation toward the first temperature-sensitive element.
US 2011/0147872 A1 discloses an optical semiconductor device, which comprises a light receiving part formed on a main surface and a transparent board laminated above the main surface, an adhesive material being interposed. The transparent board is provided with a serrated part on the main surface facing the semiconductor device and/or on the back surface.